Digital terrain analysis and long-term relief evolution of central-eastern Brazil

Abstract

Geomorphological theories for long-term relief evolution postulate the existence of planation surfaces, created by the continuouswork of erosion/deposition during periods of tectonic quiescence and recognized as extensive areas of very gentlerelief disturbed only locally by residual elevations, or by the apparent leveling of summit heights in a given region. Afterdecades since the publication of the main theories on landform evolution, the validity of these models is still an open discussion.In this paper, we present studies about the compartmentalization of landform elements, on a regional-scale basis,of central-eastern Brazil. The methods involved Digital Terrain Analysis in Geographic Information Systems, aiming theextraction and characterization of topographic variables and the compilation and mathematical analysis of geophysical andthermochronological data. Results were interpreted according to the geological context and the theories for long-term reliefevolution. The integration of morphometric, thermochronological and geophysical data does not support the validity of usingplanation surfaces in regional stratigraphic correlations.

Keywords

• Planation surface
• South American planation surface
• Geomorphology
• Digital Terrain Analysis
• Geographic Information Systems.